The present invention relates generally to wireless data transmission and, more particularly, to the use of modulated-reflector technology for full-duplex, wireless communications with remote, down-hole electronics modules. The invention also relates to the wireless transmission of electrical energy for storage at remote locations
Present day oil wells are highly sophisticated, hugely expensive operations. Modern well drilling is directionally controlled and the pipe runs can reach distances of over 25,000 feet. Platforms for off-shore wells can cost $1.5 billion apiece and must be operated at the highest levels of efficiency. Determining the down-hole conditions of a well has become a critical requirement. Conditions such as temperature, pressure, water content, salinity and others must be closely monitored. For example, as a well ages, well parameters are used to make important decisions as to how to obtain the highest yield from a particular branch of a manifold as the well""s output changes composition and performance over time. Thus, telemetry from down-hole sensors has become critical to making multi-million dollar decisions.
Reliable telemetry using electrical cables is difficult in the oil-well environment since, among other problems, cables are regularly destroyed by the harsh conditions extant down hole; for example, well temperatures can be as high as 250xc2x0 C., there is continuous, substantial abrasion by sand and dirt carried by flowing gases and liquids, and the actual cable insertion process can disrupt cable continuity.
A wireless method would be a significant improvement over the use of cables, but electricity to power normal transmissions from the sensors has not been practical without the use of wires since down-hole power sources such as batteries or capacitors need to be recharged.
Accordingly, it is an object of the present invention to communicate with down-hole sensing and monitoring equipment without the use of wires.
Another object of the invention is to provide energy to down-hole electrical equipment without the use of wires.
Still another object of the present invention is to significantly reduce energy consumption in the transmission of information from down-hole sensors.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
To achieve the foregoing and other objects, and in accordance with the purposes of the present invention, as embodied and broadly described herein, the method hereof for communicating with the distal end of an electrically conducting pipe includes the steps of: generating a radio frequency signal having a chosen frequency at the proximal end of the electrically conducting pipe such that the electrically conducting pipe radiates the signal at least in the vicinity of the distal end thereof; reflecting the radiated radio frequency signal in the vicinity of the distal end of the electrically conducting pipe such that the reflected radio frequency signal is received by the conducting pipe and transmitted to the proximal end thereof; modulating the reflected radio frequency signal in response to data received from the vicinity of the distal end of the electrically conducting pipe; and detecting the modulated, reflected signal at the proximal end of the electrically conducting pipe.
In another aspect of the present invention and in accordance with its objects and purposes the method for communicating with the distal end of an electrically conducting pipe hereof includes the steps of: generating a radio frequency signal having a chosen frequency at the proximal end of the electrically conducting pipe such that the signal remains within the electrically conducting pipe and is transmitted thereby to the distal end thereof whereafter the radio frequency signal exits the electrically conducting pipe; reflecting the radio frequency signal exiting the distal end of the electrically conducting pipe such that the reflected signal reenters the electrically conducting pipe, remains therein and is transmitted to the proximal end thereof; modulating the reflected radio frequency signal in response to data received in the vicinity of the distal end of the electrically conducting pipe; and detecting the modulated, reflected signal at the proximal end of the electrically conducting pipe.
In yet another aspect of the present invention and in accordance with its objects and purposes the method for communicating with the distal end of an electrically conducting pipe buried in the ground hereof includes the steps of: generating an electrical signal having a chosen ultra-low or extremely low frequency in the ground in the vicinity of the proximal end of the electrically conducting pipe such that the signal penetrates the ground at least to the vicinity of the buried distal end thereof; receiving the signal using the electrically conducting pipe as an antenna; modulating the impedance of the electrically conducting pipe in response to data received in the vicinity of the distal end of the electrically conducting pipe, whereby the signal received by the electrically conducting pipe is modulated; and detecting the modulated, received signal at the proximal end of the electrically conducting pipe.
In still another aspect of the present invention and in accordance with its objects and purposes the method for providing electrical energy to the distal end of an electrically conducting pipe includes the steps of: generating a radio frequency signal having a chosen frequency at the proximal end of the electrically conducting pipe such that the electrically conducting pipe radiates the signal at least in the vicinity of the distal end thereof; receiving the radio frequency signal in the vicinity of the distal end of the electrically conducting pipe; converting the radio frequency signal into dc electrical current; and storing the electrical current converted in the vicinity of the distal end of the electrically conducting pipe.
In a further aspect of the present invention and in accordance with its objects and purposes the method for providing electrical energy to the distal end of an electrically conducting pipe hereof includes the steps of: generating a radio frequency signal having a chosen frequency at the proximal end of the electrically conducting pipe such that the signal remains within the electrically conducting pipe and is conducted thereby to the distal end thereof whereafter the radio frequency signal exits the electrically conducting pipe; receiving the radio frequency signal exiting the distal end of the electrically conducting pipe; converting the received radio frequency signal into dc electrical current; and storing the electrical current in the vicinity of the distal end of the electrically conducting pipe.
In still another aspect of the present invention and in accordance with its objects and purposes the method for providing electrical energy to the distal end of an electrically conducting pipe buried in the ground hereof, includes the steps of: generating an electrical signal having a chosen ultra-low or extremely low frequency in the ground in the vicinity of the proximal end of the electrically conducting pipe such that the signal penetrates the ground to the vicinity of the buried distal end thereof; receiving the electrical signal in the vicinity of the buried distal end of the electrically conducting pipe; converting the received electrical signal into dc electric current; and storing the electrical current in the vicinity of the distal end of the electrically conducting pipe.
Benefits and advantages of the present invention include the communication with and the supply of electrical energy to down hole electronics modules without the use of wires.